1. Field of the Invention
The present invention relates to silane modified metal oxides and compositions, including chemical mechanical polishing (CMP) compositions comprising the same.
2. Description of the Related Art
Great advances are being made in the miniaturization of electronic components used in the computer and electronic industries. The miniaturization of electronic components typically involves depositing, etching and/or polishing multiple metal and oxide layers to build up an electronic substrate. Miniaturization however has created component quality concerns, many of which are overcome by precisely polishing the computer and electronic substrate materials. In order to polish electronic component surfaces precisely it has become necessary to develop chemical mechanical polishing (CMP) slurries that are compatible with the combination of surfaces being polished.
Typically, metal oxide abrasives are used in chemical mechanical polishing slurries, and several methods have been described to modify the surface chemistry of abrasive particles. For example, U.S. Pat. No. 5,645,736 discloses a method for polishing a work piece that uses organopolysiloxane polymers to disperse and hold the abrasive particles in a temporary film or matrix on the substrate being polished. Also, U.S. Pat. No. 5,767,016 discloses a polishing composition including abrasive particles that have been combined with organo metallic compounds such as -aminopropyltriethoxy silane. The particles are subsequently used in a slurry to polish a semiconductor device. In addition, U.S. Pat. No. 6,582,623 discloses CMP compositions comprising a dispersion of silane modified abrasive particles that are the product of the combination of at least one metal oxide abrasive particle including at least one surface metal hydroxide and at least one silane compound that includes at least one non-hydrolyzable substituent. Furthermore, U.S. Pat. No. 7,044,836 describes a method of polishing a substrate using a polishing composition comprising metal oxide particles having a surface with a silane compound adhered to a portion thereof a polymer adhered to the silane compound. The polymer is a water-soluble or water emulsifiable polymer. In addition, International Patent Publication No. 2007/146680 describes a stabilized silica colloid comprising a silica surface and a plurality of zwitterionic functional groups covalently bound to the silica surface, which can be used a CMP composition.
While such approaches produce useful polishing compositions, there remains a need in the industry for chemical mechanical polishing compositions comprising a metal oxide abrasive that are colloidally stable across a broad pH range.